[TinhSoSachCuaLoaiSach].sql

CREATE PROCEDURE [dbo].[TinhSoSachCuaLoaiSach]

        @MaLoaiSach char(4),

        @SoSach int OUTPUT

AS

BEGIN

SET NOCOUNT ON;

DECLARE 

        @cur_tuade CURSOR,

        @tuade char(9)

SET @SoSach = 0

SET @cur_tuade = CURSOR FORWARD_ONLY

        FOR SELECT      MaTuaDe FROM dbo.TUADESACH WHERE MaLoaiSach = @MaLoaiSach

OPEN @cur_tuade

        FETCH NEXT FROM @cur_tuade INTO @tuade

        WHILE @@FETCH_STATUS = 0

                BEGIN

                SET @SoSach = @SoSach + (SELECT COUNT(*) FROM dbo.CUONSACH WHERE MaTuaDe = @tuade)

                FETCH NEXT FROM @cur_tuade INTO @tuade

                END

CLOSE @cur_tuade

DEALLOCATE @cur_tuade

END